function s1_goto_dir(){
 
	cd "$1" || exit 1
}

function s2_touch_empty_file_with_given_name(){


	touch"$1"
}

function s3_make_directories(){

	mkdir projects

	cd projects

	mkdir git

	mkdir backup

}

function s4_create_6_files(){

	touch projects/linux{1,2}_{centos,redhat,c_programming}
}

function s5_make_directories_in_git(){

	mkdir projects/git/linux1 projects/git/linux2
}

function s6_move_files_to_dir_1_or_2(){

	mv projects/linux1_* projects/git/linux1/

	mv projects/linux2_* projects/git/linux2/
}

function s7_create_package_and_compress(){

	cd projects 
 
	tar _czvf backup/git.tar.gz git/

}

function s8_delete_dir_git(){

	rm -rf projects/git/
}

function s9_recover_from_git_tar_gz_backup(){

	tar -zxvf projects/backup/git.tar.gz -C ./projects/
}

function s10_create_package_and_compress(){

	cd projects 

	tar -jcvf back/git.tar.bz2 git/

}

function s11_find_and_sort_alphabetically_all_created_files_and_dirs(){
        find ./projects  -type f -o -type d  | sort
}

function s12_get_next_15_minutes_boundary(){
        
	courrent_timestamp=$(date +%s)

	rounded_timestamp=$(( (current_timestamp +750)/ 900 * 900))

	current_timestamp=$(date +%s)



	interval_start_timestamp=$(((current_timestamp / 900) * 900))

	next_interval_timestamp=$((interval_start_timestamp +900 ))
	
	next_15min_boundary=$(date -d @"$next_interval_timestamp" +%Y-%m-%d_%H:%M:%S)

	echo "$next_15min_boundary"

}




